Well if this is Charlie's work, because 'zerkers like to torture their victims, he wouldn't survive the flash back.

So I'm thinking it's someone trying to frame Charlie. But since it's some random guy who got strung up, no one will care. So the framer needs to step it up a bit and uses Milo as the next victim to frame Charlie.

I'm wondering if Charlie sometimes gets his mealtime blood delivered in the form of fresh corpses. In that case, this would be the part-zombie equivalent of "Oops, silly me, left the oven on."Otherwise, someone in the building's gone a bit cuckoo and now they have to play a lifesize game of Clue.